Chemical characterisation of recycled glass: from sampling to analysis by X-ray fluorescence analysis (XRF).

As improved recycling techniques have reduced contamination of glass cullet to very low levels and the percentage used in glass-making furnaces has increased to as much as 80%, it has become more important to determine the composition of foreign batches so as to guarantee that physical properties such as viscosity remain constant. Experiments are reported in which a representative sampling procedure was applied for chemical characterisation of batches from 400 to 2 000 tons. Following a number of sub-sampling steps, final sample preparation was carried out by melting a flux bead and wavelength-dispersive X-ray fluorescence analysis was applied by using a multiple-point calibration, obtained with reference materials prepared and certified in-house. The calibration and performance characteristics of the whole procedure are presented as well as several results obtained from sampling batches of soda-lime-silica glass, TV glass and TV panel and funnel glasses.
As improved recycling techniques have reduced contamination of glass cullet to very low levels and the percentage used in glass-making furnaces has increased to as much as 80%, it has become more important to determine the composition of foreign batches so as to guarantee that physical properties such as viscosity remain constant. Experiments are reported in which a representative sampling procedure was applied for chemical characterisation of batches from 400 to 2 000 tons. Following a number of sub-sampling steps, final sample preparation was carried out by melting a flux bead and wavelength-dispersive X-ray fluorescence analysis was applied by using a multiple-point calibration, obtained with reference materials prepared and certified in-house. The calibration and performance characteristics of the whole procedure are presented as well as several results obtained from sampling batches of soda-lime-silica glass, TV glass and TV panel and funnel glasses.